HP Kayak XU Technical Reference Manual page 67

PCI Interrupt Request Lines
PCI devices generate interrupt requests using up to four PCI interrupt
request lines (INTA#, INTB#, INTC#, and INTD#).
PCI interrupts can be shared; several devices can use the same interrupt.
However, optional system performance is reached when minimizing the
sharing of interrupts. Therefore, the interrupts of the PCI devices are routed
in the distributed manner, as shown below.
16-bit 8-bit
AGP
SCSI SCSI
A
A
A B
Slot 1(LAN) Slot 2
A B C D
A B C D
Slot 3 (ARO) Slot 4
A B C D A B C D
4 HP BIOS
BIOS Addresses
A
B
PCI/ISA
Bridge
C
D
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